It's called Haunted Hollow, and it's a strategic turn-based tug of war between rival Halloween monsters who want complete dominance of a tiny hamlet.

In the game, you'll build a haunted house; summon creatures like ghosts and mummies; and then attempt to scare every household in the village.

One problem: your opponent is trying to do the same thing. Actually, two problems: the town isn't going to just sit back and take it, and will unleash an angry mob that will kill anything in sight.

We went hands-on with Haunted Hollow earlier this year, and said it "might look shallow or lightweight from the outset. But once you start to see all the different strategies and play styles emerge, it becomes clear that this is very much a Firaxis game."

To learn more about this upcoming game, we sat down with creators Will Miller and David McDonough. We talked about Haunted Hollow's boardgame influences, the free-to-play approach, and going from XCOM to iPhone.

Pocket Gamer: You guys both had a hand in the development of XCOM: Enemy Unknown.

How did the experience of developing a mobile game differ from the experience of developing a big PC and console game like that?

Will Miller [WM]: Both David and I have worked on a couple of AAA titles, and going from that to mobile is different in a lot of ways, and similar in some others.

At Firaxis, we're a very iterative- and prototype-driven studio, and I don't think that changed very much. In the very early days of XCOM, it was a very prototype-driven process and it stayed that way for most of the production. Development on Haunted Hollow has been exactly the same.

We had an idea at the beginning and started immediately implementing that and iterating on that as soon as possible.

There is a difference in team size - with Haunted Hollow, it felt almost like an indie game experience. We had a very small team, and we acted very fast and loose.

David McDonough [DM]: I would re-iterate what Will said about being fast and loose. [Development on] a AAA game is slower and like moving an army, and we're more like a squad. Everybody does a lot more personally and things happen more quickly.

It's very rewarding, especially after working on AAA games, to pick up something a little more raw to work on. You know, a small project like this one.

From where did you take the inspiration for Haunted Hollow?

To me, it feels a lot like a boardgame. Were you influenced by those types of game?

DM: Boardgames were a strong influence. Both of us play a lot of boardgames. I've got quite a collection in the bookshelf behind me.

We both play a lot of mobile games, too. And to anyone who plays a lot of mobile games, the parallels are obvious. There are a lot of excellent boardgame ports and a lot of very boardgame-esque games.

We felt that the iOS platform really lends itself to games that are light and easy to understand but have a lot of subtle depth. A style of design that boardgame creators have done really well for many years.

There's a spectrum of casual to hardcore on iOS. Where do you think Haunted Hollow lies on that spectrum?

WM: We think that the aesthetics of the game certainly skew towards a much more casual experience. We did that intentionally to make it seem a little more attractive to more players than, say, a Civilization or XCOM game. Those games can look very daunting - they're strategy games, so they have lots of information and are very much catered to a particular audience.

We wanted this game to be inviting to players who have never played a Firaxis strategy game before. But we also wanted to give our core audience, and our new audience, the strategic depth for which Firaxis is famous.

We think we've struck a pretty good balance between those two things. We say around the office that Haunted Hollow is "an easy way in and a long way up". So, we want you to get in quickly, get comfortable with the game, be able to read the game easily, and start to explore a lot of the game's depth.

One of my favourite elements of the game is the angry mob, which materialises in the middle of the town and causes havoc. How did that idea come about, and how did you iterate on it?

WM: I think the mob is the single thing that we have iterated on the most in the game. It was a controversial idea from the beginning - a lot of people to whom we were going for design input and collaboration had very strong opinions about whether we should add it to the game or take it away from the game.

So, the style of the mob, and the way it impacts on the game, has changed a lot. But because it serves some important roles, we felt it had to stay in the game.

For one thing, the mob is hilarious and really helps sell the flavour of the game. You're messing with this town and it's not going to just sit there and take it.

Plus, it acts as an accelerant and a destabiliser. The game can very easily become a stalemate, especially between experienced players. The mob destabilises that and throws a wrench into your strategy.

The longer the game goes on, the more the mob starts to swing the balance of power. This helps the game come to an exciting and tense conclusion.

Haunted Hollow has been in soft launch mode in Canada for some time now. What have you learnt during this phase?

DM: The soft launch has been incredibly useful. I wish we could thank all the early adopters out there personally, as we've got a lot of great data and telemetry from watching them play.

It's the first mobile game that Firaxis has ever done and we're learning a lot, mostly about the process of iterating on a live mobile game. So, just getting the kinks worked out was very important to us.

Also, we're seeing how people are playing the game and the kinds of strategies that are emerging. We got a lot of balancing feedback, so it was very important to take it for a shakedown cruise.

The game is free. And you're charging for factions and units. How did you come to that decision?

DM: We wanted to make the game free because it's a multiplayer game. And for any multiplayer game to work, you need this critical mass of players to sustain the experience. So, F2P was a pretty obvious choice from the beginning just to ensure we get a certain number of players in the game as quickly as possible.

But despite it being a competitive game, there are some free-to-play elements that we couldn't - or didn't really want - to use, like one-off consumable items you could pay for to gain an advantage. We felt that would be unfair, so we didn't do that.

We didn't include persistent mechanics - where if you play for a longer time or invest more money than someone else, you have an edge over him - in Haunted Hollow, either. We wanted the game to be more about skill than how much money you've sunk into the game.

That said, you can diversify your play style in Haunted Hollow by paying money. So, it's like Magic: The Gathering in that respect: you could play that game pretty effectively with a starter deck, but you can really customise and specialise the way you play by buying booster packs. That's kind of the idea we embraced.

DM: There's actually an interesting parallel between that project and this one. Firaxis saw an emerging platform and an opportunity to diversify in terms of the kind of game we make.

And it was also a pet project of Sid [Meier, founder and director of creative development at Firaxis, and creator of the Civilization series). Sid was really excited about getting us to try to mash up the core gameplay of Civ and see if he could make a different kind of experience for a different kind of player.

I think the game had a lot of success in some ways, and struggled in others. It certainly was an extremely valuable experience for Sid and the Firaxis team. In the end, though, the market and the player base weren't strong enough to sustain the game.

Did Sid have any influence on Haunted Hollow? Did he provide any pearls of wisdom?

DM: Quite a few!

Sid is a godfather designer around here, and all the lead designers - us, Jake [Solomon, lead designer on XCOM: Enemy Unknown], and Ed [Beach, the current-standard bearer for the Civilization series] - have a great working relationship with Sid and regularly go to him for fireside advice on anything we're doing.

We consulted with Sid constantly on Haunted Hollow, and he played the game and provided all kinds of feedback. He advised us on the development of the game's AI for the single-player mode.

He was not personally involved in the development, but Sid's fingers are in every game that Firaxis makes. It's his philosophy that shapes all of our design.

So, as long as it's a Firaxis game, it will have a touch of Sid in it.

Haunted Hollow will be available in "the spring". It will be exclusively an iOS game at launch, but the designers told Pocket Gamer that "there's definitely interest" in producing an Android version.